The Summerwine.net locations map (accessed via the link on the main web site) shows it on Meal Hill Road, which branches off Woodhead Road west and a bit south of Holmfirth. It's the Holme Junior & Infant School, and it's web site shows the current schedule (http://www.holmejischool.co.uk/), so yes, it's still open.
When it looked different, did you see it as you passed by or did you "see" it on TV or on the internet? And was it different from the last time you saw it (or "saw" it) or from the way it appeared in the series? Just curious.